Oil VS Fuel

[thompsoncustom]

Your piston is bare because it's running rich/cool. The hotter a motor runs the more carbon is laid down. How is the saw ran, what mix and fuel and what's the current max no load rpm? A 32:1 ratio doesn't effect carbon deposition unless your running really crappy oil.
A properly designed pipe does not force exhaust into the cylinder either. A tuned pipe function by first pulling a suction on the cylinder and then by sending a return wave of fresh air/fuel back into the cylinder. If it forced exhaust back into the cylinder this would just dilute your fresh charge, which would be a step backward.

You seem pretty sure it's running cold I will have to get some temp readings from the cylinder sometime even tho i'm sure it's not I'd like to know what they are if anything it should be running hotter than a normal saw.

How is the saw ran? Hot and Hard it's only job is it cut up big limbed logs in splitable pieces fast, bar is almost always buried. Fuel is 87 pump gas at 32:1 and I have no idea what the rpms are as techs are useless for tuning so I have bothered with putting one on a saw. I will say the dyno results for the saw put it at just under 11hp and it does run a 8 pin sprocket to help keep the rpms down in the wood.

Since you seem to know how pipes work and figured on explaining it you left out that it's not 100% clean charge coming back in ever time even if the pipe is perfect. Your charge is always diluted by exhaust on a stock engine or piped but on a piped saw if your backstuffing a extra 50% air/fuel and adding a extra 5% exhaust your still power positive by alot.

It's a CPI Racing pipe custom made for the ms660.

Also the fact that you are adding more fuel and air each time would speed up the process of carbon building up unless maybe because of the higher cylinder pressure the fuel burns cleaner.

"unless your running really crappy oil" Maybe that's my secret to spotless chainsaw engines as I use the same cheap boat motor oil on everything. But I can get some pics of the piston as i'm sure it's flawless if it wasn't performing 100% it would be toast pretty quick at this power/rpm level. Even if the saw died at this point the money saved from the cheaper mix would pay for a new saw so I'm in the green either way it's not a family heirloom just a tool.

 

[Breckinridge Elkins]

Hold on a second I thought it was fuel, not oil that cools an engine?

 

[Riverrail]

VP.
Edited: I've also ran a few gallons of Rural King in the saw only.
To be clear I am buying the non mixed four stroke akylate and then mixing my own oil(red armor) with it.

From what I’ve recently tried to find out, the only actual alkylate fuels I’ve found are Aspen and Stihl Motomix. The others are distillates and do not burn clean like true alkylates.

VP.
Edited: I've also ran a few gallons of Rural King in the saw only.
To be clear I am buying the non mixed four stroke akylate and then mixing my own oil(red armor) with it.

 

[Vintage Engine Repairs]

From what I’ve recently tried to find out, the only actual alkylate fuels I’ve found are Aspen and Stihl Motomix. The others are distillates and do not burn clean like true alkylates.

This is how I understand it too, truefuel is an example of this. I have had a look at VP and they don’t mention what the composition of their fuel is, though I don’t see anywhere it mention it’s alkylate.

 

[Tomos770]

From what I’ve recently tried to find out, the only actual alkylate fuels I’ve found are Aspen and Stihl Motomix. The others are distillates and do not burn clean like true alkylates.

I think that Huskys engineered fuel is also repacked Aspen....cans look the same.....and Husky also endorse Aspen use all the time...

Edit: fuel cans can vary in apperance locally....

https://www.willisandgrabham.co.uk/category/aspen-fuel

 

[Vintage Engine Repairs]

Tom, I'll do you one better. Get in a plane and come over here and I'll let you run any of my 1/5 scale and even take you down to wangner park for a race. There's a great 23-26cc on road stock class. I quite assure you they tach 20k down the straightaway.

Sean, what engine (make and model) are you running that does 20k loaded.

 

[Riverrail]

I think that Huskys engineered fuel is also repacked Aspen....cans look the same.....and Husky also endorse Aspen use all the time...

Edit: fuel cans can vary in apperance locally....

https://www.willisandgrabham.co.uk/category/aspen-fuel

From what I found out on websites and cans, Husky, Trufuel, VP and HarvestKing are all distillate based fuels.

 

[OM617YOTA]

Trufuel is alkylate according to their safety data sheet.

 

[Vintage Engine Repairs]

Trufuel is alkylate according to their safety data sheet.

It contains other petrochemicals too - it’s not fully alkylate / as refined as aspen or motomix.

 

[bwalker]

From what I’ve recently tried to find out, the only actual alkylate fuels I’ve found are Aspen and Stihl Motomix. The others are distillates and do not burn clean like true alkylates.

VP is alkylate for certain and alkylate is a distillate... Their are other refinery streams that are as high quality as alkylate. Reformate being one of them. It would actually be beneficial to have a blend of streams vs straight alkylate in a two stroke anyways.
The other rural king product I used a small amount of smelled just like the VP stuff and I wouldn't be suprised if VP made it. VP makes most of the canned fuel in the US from what I gather.

 

[bwalker]

It contains other petrochemicals too - it’s not fully alkylate / as refined as aspen or motomix.

Another BS post from you. You don't know the differance in refinery streams, their quality, or why they are blended so why comment?
And FWIW Aspen isn't straight alkylate either as I just looked at the MSDS file. And for good reason I might add.

 

[bwalker]

You seem pretty sure it's running cold I will have to get some temp readings from the cylinder sometime even tho i'm sure it's not I'd like to know what they are if anything it should be running hotter than a normal saw.

How is the saw ran? Hot and Hard it's only job is it cut up big limbed logs in splitable pieces fast, bar is almost always buried. Fuel is 87 pump gas at 32:1 and I have no idea what the rpms are as techs are useless for tuning so I have bothered with putting one on a saw. I will say the dyno results for the saw put it at just under 11hp and it does run a 8 pin sprocket to help keep the rpms down in the wood.

Since you seem to know how pipes work and figured on explaining it you left out that it's not 100% clean charge coming back in ever time even if the pipe is perfect. Your charge is always diluted by exhaust on a stock engine or piped but on a piped saw if your backstuffing a extra 50% air/fuel and adding a extra 5% exhaust your still power positive by alot.

It's a CPI Racing pipe custom made for the ms660.

Also the fact that you are adding more fuel and air each time would speed up the process of carbon building up unless maybe because of the higher cylinder pressure the fuel burns cleaner.

"unless your running really crappy oil" Maybe that's my secret to spotless chainsaw engines as I use the same cheap boat motor oil on everything. But I can get some pics of the piston as i'm sure it's flawless if it wasn't performing 100% it would be toast pretty quick at this power/rpm level. Even if the saw died at this point the money saved from the cheaper mix would pay for a new saw so I'm in the green either way it's not a family heirloom just a tool.

I am certain it's running cool.
As for your comments on pipes. A two stroke, pipe or not will have some residual exhaust gas in the combustion chamber. A pipe lessons this amount. It doesn't increase it assuming the pipe is properly designed for the motor. And designing a pipe for a chainsaw that's operated in a very narrow rpm range and without being on and off the throttle constantly like a MX bike is pretty easy and as such you should saw less residual exhaust gas in the combustion chamber. You certainly shouldn't be pushing exhaust into the cylinder with a properly designed saw pipe.
If your burning hydrocarbons you are producing carbon period. The higher the temp the more that are deposited.
Running boat oil in a air cooled motor is stupid. Their is no upside and plenty of downside.
And tachs are very useful for tuning motors. Much more precise and repeatable than using your ear.

 

[Vintage Engine Repairs]

Another BS post from you. You don't know the differance in refinery streams, their quality, or why they are blended so why comment?
And FWIW Aspen isn't straight alkylate either as I just looked at the MSDS file. And for good reason I might add.

No need for the childish insults, you think a rich engine doesn’t produce carbon and a lean one is the only one that does, when there are so many more factors you’re ignoring from fuel quality, age, load, application, elevation, oil, but what should be a red flag is your saws running engineered fuel and your equipment is as dirty as one that runs pump gas…

Read the MSDS, compare to motomix or aspen. Trufuel contains both olefins and aromatics, motomix and aspen don’t. I repeat, aspen / motomix are more refined. You insult your way through each post which is a sign you have nothing else to offer. As much as 20% of trufuel is a combination of toluene, xylene & benzene.





Tru fuel


Motomix

 

[OM617YOTA]

Interesting. Good data, @Vintage Engine Repairs. Rather not have the xylene and toluene.

Pentane is another name for methylbutane, which means Motomix and TruFuel are very largely the same fuel.

I'll be sticking with TruFuel, due to being available in the richer ratios I prefer, using a Jaso FD oil instead of Ultra, and lower cost.

 

[thompsoncustom]

No need for the childish insults, you think a rich engine doesn’t produce carbon and a lean one is the only one that does, when there are so many more factors you’re ignoring from fuel quality, age, load, application, elevation, oil, but what should be a red flag is your saws running engineered fuel and your equipment is as dirty as one that runs pump gas…

Read the MSDS, compare to motomix or aspen. Trufuel contains both olefins and aromatics, motomix and aspen don’t. I repeat, aspen / motomix are more refined. You insult your way through each post which is a sign you have nothing else to offer. As much as 20% of trufuel is a combination of toluene, xylene & benzene.

View attachment 1113288



Tru fuel
View attachment 1113280

Motomix

View attachment 1113281

Nice, ya there is so much that goes into it some more are compression, chamber shape/size, peak cylinder pressure, turbulence. I'm sure the list goes on and on.

You certainly shouldn't be pushing exhaust into the cylinder with a properly designed saw pipe.

The overall all exhaust volume goes up but the percentage goes down of fuel/air to exhaust it would be nice if there was no mixing of air/fuel and exhaust when it's in the pipe before it's jammed back into the chamber but that's just not how it works.

Running boat oil in a air cooled motor is stupid. Their is no upside and plenty of downside.

Maybe but according to you it sounds amazing. You said the engine is really colder than it should be and I looked there's no carbon build up, piston and cylinder show no signs of unusual wear and the saw is running at top performance so what's not to love.

And tachs are very useful for tuning motors. Much more precise and repeatable than using your ear.

No tachs are useful for replicating someone else's tune on a stock saw. Stihl tech develops a tune and detunes it a little for safety and then you take his numbers and plug them in...that's not tuning.

How would you use a tach to "tune" a saw that has been ported and piped at 5000ft elevation on a 100 degree day? Obviously there's no reference point for you to plug in here.

 

[bwalker]

Nice, ya there is so much that goes into it some more are compression, chamber shape/size, peak cylinder pressure, turbulence. I'm sure the list goes on and on.


The overall all exhaust volume goes up but the percentage goes down of fuel/air to exhaust it would be nice if there was no mixing of air/fuel and exhaust when it's in the pipe before it's jammed back into the chamber but that's just not how it works.

Maybe but according to you it sounds amazing. You said the engine is really colder than it should be and I looked there's no carbon build up, piston and cylinder show no signs of unusual wear and the saw is running at top performance so what's not to love.

No tachs are useful for replicating someone else's tune on a stock saw. Stihl tech develops a tune and detunes it a little for safety and then you take his numbers and plug them in...that's not tuning.

How would you use a tach to "tune" a saw that has been ported and piped at 5000ft elevation on a 100 degree day? Obviously there's no reference point for you to plug in here.

Running a overly cool engine is only indicative of poor tuning.

The pipe function is as I described..
A tach is very useful for tuning. You do this by fine tuning the saw for peak speed in the wood your cutting. Then record the max no load rpm. Going forward you can hit it bang on every time with a tach.

 

[bwalker]

No need for the childish insults, you think a rich engine doesn’t produce carbon and a lean one is the only one that does, when there are so many more factors you’re ignoring from fuel quality, age, load, application, elevation, oil, but what should be a red flag is your saws running engineered fuel and your equipment is as dirty as one that runs pump gas…

Read the MSDS, compare to motomix or aspen. Trufuel contains both olefins and aromatics, motomix and aspen don’t. I repeat, aspen / motomix are more refined. You insult your way through each post which is a sign you have nothing else to offer. As much as 20% of trufuel is a combination of toluene, xylene & benzene.

View attachment 1113288



Tru fuel
View attachment 1113280

Motomix

View attachment 1113281

You are reading an MSDS but have no clue what your looking at. Similar MO to your You tube videos.
I make fuel for a living. In addition I have been racing, tuning and fooling with two strokes in general since the 90's. I have also blended my own fuels starting in the 90's to skirt racing rules. Inwas belnding isoprene and MTBE/ETBE in fuel before most knew what they were.
My equipment isn't dirty at all. It actually is text book perfect. You just don't have any idea what a properly tuned motor should look like. Like zero clue.
And I get a kick out of your "more refined". People that use such verbiage don't have a clue what they are talking about. Modern diesel fuel is highly refined yet won't burn clean in a gasoline engine, if at all. CAT cracked gas is highly refined yet it is also high unstable and tends to form gums and varnish. Once again you have no idea what constitutes a good fuel or not.
Regardless what ever magic fuel you use you will have a carbon coated piston if you are tuned properly minus a slight amount of wash where the transfers discharge. That you don't know this is very telling. IE you don't know what the heck your talking about, just like most You tube "experts".

 

[bwalker]

And BTW aspen contains isomerate. What do you suppose that is.
Aspen MSDS followed by isomerate msds.

 

[Riverrail]

I've not seen that with alkylate fuels at all.

I recently watched a video on here from a year or two ago, but try as I may I can’t seem to find it now. The video showed carbon deposits from six different engineered fuels in reasonably identical chainsaw tests. Aspen and Motomix showed no carbon deposits after 2 gallons of cutting. Trufuel, VP, Husqvarna, and one other brand all showed what is considered normal carbon deposits for a well tuned saw. Same saw with new innards for each test.

 

[bwalker]

I recently watched a video on here from a year or two ago, but try as I may I can’t seem to find it now. The video showed carbon deposits from six different engineered fuels in reasonably identical chainsaw tests. Aspen and Motomix showed no carbon deposits after 2 gallons of cutting. Trufuel, VP, Husqvarna, and one other brand all showed what is considered normal carbon deposits for a well tuned saw. Same saw with new innards for each test.

Than they are running rich or a large portion of the fuel isnt combusting... Different fuels have different tuning requirements. And motomix shows the most carbon in the video posted below... I don't put alot of stock in that as the test was fairly limited in length. In time all would show a piston covered in carbon minus transfer was at the discharge points.
This is the test you might be referring to: